Rapid and precise epitope mapping of monoclonal antibodies against Plasmodium falciparum AMA1 by combined phage display of fragments and random peptides

We describe an approach for the rapid mapping of epitopes withina malaria antigen using a combination of phage display techniques.Phage display of antigen fragments identifies the location ofthe epitopes, then random peptide libraries displayed on phageare employed to identify accurately amino acids involved inthe epitope. Finally, phage display of mutant fragments confirmsthe role of each residue in the epitope. This approach was appliedto the apical membrane antigen-1 (AMA1), which is a leadingcandidate for inclusion in a vaccine directed against the asexualblood stages of Plasmodium falciparum. As part of the effortboth to understand the function of AMA1 in the parasite lifecycle and to define the specificity of protective immune responses,a panel of monoclonal antibodies (MAbs) was generated to obtainbinding reagents to the various domains within the molecule.There is a pressing need to determine rapidly the regions recognizedby these antibodies and the structural requirements requiredwithin AMA1 for high affinity binding of the MAbs. Using phagedisplaying random AMA1 fragments, it was shown that MAb5G8 recognizesa short linear epitope within the pro-domain of AMA1 whereasthe epitope recognized by MAb 1F9 is reduction sensitive andresides within a disulphide-bonded 57 amino acid sub-domainof domain-1. Phage displaying random peptide libraries and mutantAMA1 fragments were employed for fine mapping of the MAb5G8core epitope to a three-residue sequence in the AMA1 prodomain.     

Application of a CCA-treated wood waste decontamination process to other copper-based preservative-treated wood after disposal

Chromated copper arsenate (CCA)-treated wood was widely used until 2004 for residential and industrial applications. Since 2004, CCA was replaced by alternative copper preservatives such as alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ), for residential applications due to health concerns. Treated wood waste disposal is becoming an issue. Previous studies identified a chemical process for decontaminating CCA-treated wood waste based on sulfuric acid leaching. The potential application of this process to wood treated with the copper-based preservatives (alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ)) is investigated here. Three consecutive leaching steps with 0.1 M sulfuric acid at 75°C for 2 h were successful for all the types of treated wood and achieved more than 98% copper solubilisation. The different acidic leachates produced were successively treated by coagulation using ferric chloride and precipitation (pH=7) using sodium hydroxide. Between 94 and 99% of copper in leachates could be recovered by electrodeposition after 90 min using 2 A electrical current. Thus, the process previously developed for CCA-treated wood waste decontamination could be efficiently applied for CA-, ACQ- or MCQ-treated wood.     

Organization and expression of the mitochondrial genome in the Nicotiana sylvestris CMSII mutant

Previous analyses suggested that the Nicotiana sylvestris CMSII mutant carried a large deletion in its mitochondrial genome. Here, we show by cosmid mapping that the deletion is 60 kb in length and contains several mitochondrial genes or ORFs, including the complex I nad7 gene. However, due to the presence of large duplications in the progenitor mitochondrial genome, the only unique gene that appears to be deleted is nad7. RNA gel blot data confirm the absence of nad7 expression, strongly suggesting that the molecular basis for the CMSII abnormal phenotype, poor growth and male sterility, is the altered complex I structure. The CMSII mitochondrial genome appears to consist essentially of one of two subgenomes resulting from recombination between direct short repeats. In the progenitor mitochondrial genome both recombination products are detected by PCR and, reciprocally, the parental fragments are detected at the substoichiometric level in the mutant. The CMSII mtDNA organization has been maintained through six sexual generations.     

Context and cue cards in young children's testimony: A comparison of brief narrative elaboration and context reinstatement.

In a comparison of interview procedures that aimed to assist retrieval strategies in children's event recall, 72 children aged 4-6 years were questioned about a witnessed event. Context reinstatement and brief narrative elaboration (an abbreviated version of K. J. Saywitz and L. Snyder's [1996] procedure) produced similar levels of correct recall, and both elicited more correct recall than did a control condition, with no increase in errors. Combining these procedures did not further improve performance. The superiority of narrative elaboration over the control group was evident in free recall and did not depend on explicit prompting with cue cards. These findings suggest that incorporating brief narrative elaboration training in investigative interviews with children may, like context reinstatement, be a valuable mnemonic aid. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

University Instructors' Acceptance of Electronic Courseware: An Application of the Technology Acceptance Model

This study examines the factors that influence instructors' adoption and use of an Internet-based course management system and tests the applicability of the Technology Acceptance Model (TAM), introduced by Davis (1986) , in the context of e-learning practices in higher education. Using data from an online survey of a university's instructors ( N = 191), a path analysis revealed that perceived ease of use of the system had a significant impact on perceived usefulness as the TAM suggested. In addition, a direct effect of perceived usefulness on behavioral intention to use and an indirect effect of the variable on actual system use, both of which were proposed in the TAM, were also found. Further, motivation to use the system played a significant role in affecting perceived ease of use, perceived usefulness, evaluation of functions, current system use, and behavioral intention to keep using the system. This study suggests that integration of the TAM and the uses and gratification approach can be fruitful for future research on the diffusion of Internet-based technological systems.     

Evaluation of the MODIS LAI algorithm at a coniferous forest site in Finland

Leaf area index (LAI) collected in a needle-leaf forest site near Ruokolahti, Finland, during a field campaign in June 14-21, 2000, was used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) LAI algorithm. The field LAI data was first related to 30-m resolution Enhanced Thermal Mapper Plus (ETM+) images using empirical methods to create a high-resolution LAI map. The analysis of empirical approaches indicates that preliminary segmentation of the image followed by empirical modeling with the resulting patches, was an effective approach to developing an LAI validation surface. Comparison of the aggregated high-resolution LAI map and corresponding MODIS LAI retrievals suggests satisfactory behavior of the MODIS LAI algorithm although variation in MODIS LAI product is higher than expected. The MODIS algorithm, adjusted to high resolution, generally overestimates the LAI due to the influence of the understory vegetation. This indicates the need for improvements in the algorithm. An improved correlation between field measurements and the reduced simple ratio (RSR) suggests that the shortwave infrared (SWIR) band may provide valuable information for needle-leaf forests.     

Ultra performance liquid chromatographic profiling of serum N-glycans for fast and efficient identification of cancer associated alterations in glycosylation

Glycosylation is a diverse but critically important post-translational modification that modulates the physical, chemical and biological properties of proteins. Alterations in glycosylation have been noted in a number of diseases including cancer. The discovery of alterations in the glycosylation of serum glycoproteins which may offer potential as biomarkers is attracting considerable research interest. In the current study, the significant improvements in efficiency, selectivity, and analysis speed offered by ultra performance liquid chromatography (UPLC) profiling of fluorescently labeled N-linked oligosaccharides on a recently introduced sub-2 μm hydrophilic interaction (HILIC) based stationary phase are demonstrated to identify cancer associated alterations in the serum N-glycome of patients bearing stomach adenocarcinoma. The contribution of the glycosylation present on four highly abundant serum proteins namely, IgG, haptoglobin, transferrin, and α1-acid glycoprotein was evaluated. Alterations in the glycosylation present on these four proteins isolated from the pathologically staged cancer serum using either affinity purification or two-dimensional electrophoresis were then investigated as possible markers for stomach cancer progression. In agreement with previous reports, an increase in sialylation was observed on haptoglobin, transferrin, and α1-acid glycoprotein in the cancerous state. Increased levels of core fucosylated biantennary glycans and decreased levels of monogalactosylated core fucosylated biantennary glycans were present on IgG with increasing disease progression. The speed and selectivity offered by the sub-2 μm HILIC phase make it ideal for rapid yet highly efficient separation of complex oligosaccharide mixtures such as that present in the serum N-glycome.